Devices and methods for accessing the vasculature of a patient

ABSTRACT

A steerable guide sheath system adapted for delivery into a patient&#39;s vasculature. The pull wire which is used to tension the deflectable portion of the sheath is wrapped or twisted around the axis of the sheath.

This application is a continuation-in-part of U.S. application Ser. No.14/798,181, filed Jul. 13, 2015, which is a continuation of U.S.application Ser. No. 13/965,807, filed Aug. 13, 2013, now U.S. Pat. No.9,078,994, which is a division of U.S. application Ser. No. 12/177,338,filed Jul. 22, 2008, now U.S. Pat. No. 8,939,960, which is acontinuation of U.S. application Ser. No. 11/016,448 filed Dec. 17, 2004now U.S. Pat. No. 7,402,151, each of which is hereby incorporated byreference, in its entirety. This application is also acontinuation-in-part of U.S. application Ser. No. 13/288,918, filed Nov.3, 2011, which claims priority to Provisional Patent Application61/409,929 filed Nov. 3, 2010, each of which is hereby incorporated byreference, in its entirety.

FIELD OF THE INVENTIONS

The inventions described below relate the field of steerable guidecatheters and sheaths.

BACKGROUND OF THE INVENTIONS

Guide catheters are used to gain access to the desired target locationwithin the vasculature of a patient and provide a safe, smooth conduitto guide and support another device, such as an interventional catheter,to the target location. A guide catheter is typically inserted into thebody through an introducer sheath and over a guidewire. Guidewires arelong coiled wire structures that can be navigated through thevasculature and then used to lead another device through thevasculature. The guided device is typically the delivery device thatcarries an implant for deposit in the vasculature, an active device thatcarries out the diagnosis, therapy or intervention. Guide catheters canalso be used to pass fluids for visualization, diagnosis or treatment.

A sheath is a type of guide catheter that also seals the entry point inthe vascular space. The sealing is usually accomplished with a valve onthe back of the sheath that either passively opens and closes whendevices are inserted into it, or is opened and closed manually by thedoctor when a device is inserted into it. The sheath protects the vesselfrom damage that might be caused by the guide or device that is passedwithin the sheath. Sheaths are typically thinner-walled and moreflexible than guide catheters. They are typically straight-ended and maybe inserted into the vessel over a guidewire or an introducer/obturator.An obturator/introducer is typically a long plastic tube with a distaltapered end that is longer than the device into which it fits andcontains a central lumen to track over a guidewire. The obturator isusually flexible enough to allow the insertion of the device over itinto a vessel or through a hemostatic valve and rigid enough tostraighten out any pre-shaped guide that is over it.

Over the years, many guide catheters have been developed for treatingspecific diseases, delivering specific devices, or for accessingspecific locations within the body. These guides are typically PTFElined devices with walls made from a composite of thermoplastics andmetal wire braid and coil reinforcements. They are thin-walled andflexible, but can transmit some torque from the proximal end to thedistal end to allow the doctor to steer the distal end to the locationof interest. Most guide catheters have a specific pre-formed shape thatallows them to perform their narrow function and only their narrowfunction. They have been developed and customized over the years toreach one specific anatomic location only. The variety of achievableshapes is also limited because the guide must be inserted into the bodyin the straight configuration, so that the guide can be advanced to thelocation of interest without dragging or scraping along the vesselwalls. Once at the desired location, the guide typically retakes itsshaped configuration when the obturator or guidewire is removed from it.This flexibility detracts from the guide's ability to supportinterventional devices that are inserted through it. Also, the curvatureof a pre-shaped guide must be limited, or it will not straighten outwhen the obturator is inside of it. These limitations of fixed shapeguides point to a need for improved devices to enable atraumatic accessto the target locations of interest.

A typical use of these devices is in interventional cardiology to treata plaque build up or blockage in a patient's coronary artery. Theseblockages can lead to heart attacks and death. Typically, a patientpresenting with symptoms is investigated with EKG tracings, a stresstest or angiography (imaging with moving x-ray pictures and radiopaquefluids). In order to complete an angioplasty, the doctor would locate afemoral artery under the skin in the groin and install a sheath into anarterial opening, such as an 8 French sheath. The distal end of thesheath stays inserted into the artery and the proximal end, which has ahemostatic valve on it, remains outside the body. The surgeon would theninsert a guide catheter that has a guidewire inside it through thesheath and into the femoral artery. Visualizing the devices onfluoroscopy, the surgeon manipulates the tip of the guide and guidewireretrograde up the aorta until he can engage the ostium of the coronaryartery that has the suspected blockage in it. The surgeon then advancesthe guidewire into the artery toward the lesion of interest. Afteridentifying the lesion location with angiography, the surgeon introducesan angioplasty balloon catheter into the guide (may or may not be overthe guidewire inside the guide) and advances the angioplasty balloon tothe lesion site. When correctly located, the surgeon inflates theballoon on the end of the angioplasty catheter to push the plaque backagainst the artery walls, thereby alleviating the blockage in thevessel. Once the procedure is completed, he removes the angioplastycatheter, guide, guidewire and sheath and disposes of them. Theprocedure for implanting a stent in the body is very similar to thepreviously described angioplasty procedure. After inflating a balloon topush the plaque against the wall of the vessel, the doctor inflates orexpands a stent, which is left permanently behind in the vessel.

Interventional cardiologists now have procedures and differentspecifically shaped guides for the left and right coronary arteries,renal arteries, carotid arteries, internal mammary arteries, abdominalaorta, hepatic arteries and veins, pulmonary arteries, and veins, theatria and ventricles of the heart, mesenteric arteries, femoralarteries, neurological locations, and the coronary sinus of the heart.In many of the procedures, the fixed shape of the guide is not quiteright for the patient anatomy and the surgeon must wrestle to get theguide into position, or discard the guide and try another shape. Thisconsumes significant time in the catheterization lab which has coststoday that run roughly $20 per minute. Although fixed guide cathetersare relatively cheap medical devices today, the inability to access atarget site in the body quickly due to anatomical variation or thepropagation of disease can quickly cost hundreds of dollars. Extensivetime in a fluoroscopy suite also exposes the physician and the patientunnecessarily high doses of radiation.

There are a small number of new guide catheters whose shape can bechanged by the operator during surgery. These are called deflectableguide catheters. Their shape-changing ability allows them to be adjustedby the surgeon during a procedure to fit the anatomy of the patient,which normally varies due to disease, body type, genetics and otherfactors.

For example, Badger, Guiding Catheter With Controllable Distal Tip, U.S.Pat. No. 4,898,577 (Feb. 6, 1990) and Badger, Guiding Catheter WithControllable Distal Tip, U.S. Pat. No. 5,030,204 (Jul. 9, 1991) describea steerable guide catheter with and outside diameter of 0.118″ and aninside diameter of 0.078″. A number of US, European and Japanese patentsissued to Lundquist including U.S. Pat. Nos. 5,685,868, 5,228,441,5,243,167, 5,322,064, 5,329,923, 5,334,145, 5,454,787, 5,477,856,5,685,868, EP521595B1, JP 7255855A2, describe the use of slotted metaltubes such as nitinol torque tube elements in steerable catheters.Rosenman, Drug Delivery Catheters That Attach To Tissue And Methods ForTheir Use, U.S. Pat. No. 6,511,471 (Jan. 28, 2003)(the entirety of whichis hereby incorporated by reference) describes a steerable guidecatheter for delivering a medical device within the ventricle of theheart using the slotted Nitinol torque tube technology of Lundquist witha relatively large catheter lumen as it was used to pass other medicaldevices.

Qin, Deflectable Guiding Catheter, U.S. Pat. No. 6,251,092 (Jun. 26,2001) describes a deflectable guide catheter whose deflection point isproximal from the distal tip. This patent does not enable a tight radiusbending deflectable guide catheter that can track over a guidewire tolocations of interest in the vascular tree in patients.

Farmholtz, Torqueable And Deflectable Medical Device Shaft, U.S. Pat.No. 6,716,207 (Apr. 6, 2004) describes a steerable catheter with slitsin a tube component in the shaft. However, the bending point of thiscatheter is proximal of the end of the catheter, which results in alarge sweep distance during bending, which is not desirable. Also, thiscatheter has a stiffer braided portion distal to the bending section,which decreases the trackability of the catheter. Also, this patent doesnot enable the construction of the shaft with a large central lumen ordetail the cross sectional construction.

The ideal guide catheter is one that can adjust for varying patientanatomies while maintaining a thin wall and providing enough support forthe devices passed through it to their target locations in the body. Itshould be smooth and lubricious on the inside and the outside surface.It should be stiff enough in torque to allow the doctor to direct thedistal tip by manipulating the handle outside of the body. Minimizingthe outside diameter of a guide catheter is important to minimize thesize of the opening made in the patient's vessel to gain vascularaccess, and also to enable the distal portion of the device to beadvanced through smaller vessels. Smaller openings are easier to closeafter the procedure and have less post-procedure healing complications.It is also important to have a large internal diameter in a device toallow easy passage of other interventional devices. The ideal guidecatheter should be compatible with commonly used interventionalguidewires, angioplasty balloon catheters, stent catheters andhemostatic introducer sheaths. The ideal catheter should also be visibleon fluoroscopy and usable in an MRI suite.

SUMMARY

The devices and methods described below provide for easy, atraumaticaccess to areas of the vasculature that are otherwise difficult toaccess. The steerable guide catheters described below are constructedwith components that are selected to provide optimal navigability,torque transfer, and push ability for a variety of typical percutaneousaccess routes. The steerable guide catheters enable percutaneous routessuch as femoral artery approaches to the renal arteries, contralateralfemoral artery, carotid arteries, and venous approaches to the fossaovalis, the coronary sinus, etc. The catheter wall thickness in thedeflecting segment of the guide catheter is about 1 French (⅓ mm) orless, and includes a slotted deflection tube, and this constructionallows a very tight turning ratio which in turn enables guide catheteraccess to regions of the vasculature that are otherwise inaccessible.Furthermore, addition of the deflection capability distal to a preformedcatheter shaft bend or proximal to a preformed catheter shaft may helpoptimize catheter shape and steerability for many interventionalapplications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the deflectable guide catheter with the tip in itsstraight configuration.

FIG. 2 illustrates the deflectable guide catheter with the tip in itsbent configuration.

FIG. 3 is a cutaway view of the distal end of the deflectable guide inFIG. 1.

FIG. 4 is a plan view of a nitinol deflection tube of the deflectableguide catheter.

FIG. 4a , which shows an embodiment in which a section of a pull wiretube is twisted around the inner tube.

FIG. 5 is a cross section of the distal end of the tubing of thedeflectable guide catheter shown in FIG. 1.

FIG. 6 is a cross section of the proximal portion of the tubing of thedeflectable guide catheter shown in FIG. 1.

FIG. 7 is a schematic of a deflectable guide catheter in the bodyvasculature accessing a carotid artery from a femoral access site.

FIG. 7a illustrates the deflectable guide catheter adapted for accessinga carotid artery from a femoral access site.

FIG. 8 is a schematic of a deflectable guide catheter in the bodyvasculature accessing a renal artery from a femoral access site.

FIG. 8a illustrates the deflectable guide catheter adapted for accessinga renal artery from a femoral access site.

FIG. 9 is a schematic of a deflectable guide catheter in the bodyvasculature going from one side of the femoral aortic bifurcation to theother, around the horn.

FIG. 9a illustrates the deflectable guide catheter adapted for crossingthe femoral aortic bifurcation.

FIGS. 9b, 9c and 9d illustrate variations of the deflectable guidecatheter adapted for crossing the femoral aortic bifurcation.

FIG. 10 is a schematic of a deflectable guide catheter in the bodyvasculature accessing the left internal mammary artery from a femoralaccess site.

FIG. 10a illustrates the deflectable guide catheter adapted foraccessing the left internal mammary artery from a femoral access site.

FIG. 11 is a schematic of a deflectable guide catheter in the bodyvasculature accessing the coronary sinus in the right atrium from avenous access site in the neck of the body.

FIG. 11a illustrates the deflectable guide catheter adapted foraccessing the coronary sinus in the right atrium from a venous accesssite in the neck of the body.

FIG. 12 is a schematic of a deflectable guide sub-selecting a coronaryvein from within another deflectable guide that is accessing thecoronary sinus from a venous access site in the neck of a body.

FIG. 12a illustrates the deflectable guide catheter adapted foraccessing a coronary vein from a venous access site in the neck of thebody.

FIG. 13 is a schematic of a deflectable guide catheter in the bodyvasculature accessing the left coronary artery ostium in the aorta froma femoral arterial access site.

FIG. 13a illustrates the deflectable guide catheter adapted foraccessing the left coronary artery ostium in the aorta from a femoralarterial access site.

DETAILED DESCRIPTION OF THE INVENTIONS

FIG. 1 illustrates the deflectable guide catheter with the tip in itsstraight configuration. The guide catheter 1 comprises a steerable guidecatheter tube 2 with a catheter handle 3 mounted on the proximal end 4of the guide catheter tube. The distal end of the guide catheter tubeincludes a deflectable segment 5 which is operated by a pullwire viamanipulation of a steering lever 6 on the proximal handle. Asillustrated in FIG. 2, the deflectable segment is bent in an arc as thesteering lever turned by the operator.

FIG. 3 is a cutaway view of the distal end of the deflectable guide inFIG. 1. As shown in FIG. 3, the deflectable segment of the guidecatheter tube 2 is comprised of an outer catheter shaft 7 and a catheterinner tube 8, with a deflection tube 9 sandwiched between the two. APTFE liner 10 is disposed within the catheter inner tube 8. That portionof the catheter inner tube 8 which resides inside the deflection tube(item 8 d) comprises a coil covered with pebax. The portion of thecatheter inner tube 8 which is proximal to the deflection tube (item 8p) comprises a braid covered with pebax or embedded with pebax. Itsouter diameter is sized to slip fit within the inner diameter of theouter catheter shaft 7. A pullwire 11 runs between the innercatheter/deflection tube and the outer catheter shaft 7. A groove forreceiving the pullwire may be cut in the outer wall of the inner tube orin the inner wall of the outer catheter shaft. The two shafts may thenbe melted, bonded, pull-truded, glued or welded to make a unitary tubewith a central lumen and an eccentric pullwire lumen.

FIG. 4 is a plan view of a nitinol deflection tube of the deflectableguide catheter. The deflection tube 9 consists of a round stainlesssteel or nitinol tube with a specific pattern of slots 12 machined intoit as shown in FIG. 4. The pattern of slots controls the shape that thedistal portion of the catheter bends in and the sequence in which itssections bend. The slots 12 are cut to varying depths, widths andspacing to control the shape of the tube's bending. Slots may alsoinclude angular variations. Angular variations allow one to createflexibility in many directions, create three dimensional curvegeometries, and create multiple deflecting segments in the samedeflection component which can be controlled by separate pull wireswhich may used create curves in different planes from one another.

FIG. 5 is a cross section of the distal end of the tubing of thedeflectable guide catheter shown in FIG. 1, illustrating the pebaxcovered coil 8, which may be reinforced with metal braid, immediatelysurrounding the PTFE liner 10 the deflection tube 9 immediatelysurrounding the catheter and catheter inner tube 8 d and liner 10, andthe catheter outer tube 7 with the pullwire 11 running between thedeflection tube and the catheter inner tube 8 d. The outer cathetershaft comprises a braided tube 13 covered in an outer jacket 14. FIG. 6is a cross section of the proximal portion of the tubing of thedeflectable guide catheter shown in FIG. 1, illustrating the PTFE liner10, the catheter inner tube 8 p immediately surrounding the liner (pebaxand braid, which is roughly isodiametric with the covered coil), and thecatheter outer tube 7 with the pullwire running between the deflectiontube and the outer catheter shaft. The outer catheter shaft comprises astainless steel braided tube 13 covered in the outer jacket 14 pebax.The basic structure of the steerable guide catheter may be modified asdescribed below to enable an easily navigable guide catheter suited toaccess various target locations within the vasculature.

Carotid Artery Deflectable Guide/Guide-Sheath

FIG. 7 is a schematic of a deflectable guide catheter in the bodyvasculature accessing a carotid artery from a femoral access site, whileFIG. 7a illustrates the deflectable guide catheter adapted for accessinga carotid artery from a femoral access site. The carotid artery is inthe neck. It may be narrowed or occluded by plaque, which limits theamount of blood flowing to the brain. Doctors may want to intervene inthe carotid artery to enlarge the lumen and increase the flow of bloodto the brain. Carotid stenting is an important new interventionalmodality with the primary difficulty today being vascular access. Asundue manipulation in such a procedure could dislodge plaque from thevessel with severe downstream repercussions of embolic stroke inducedneurological deficit costing upwards of $50,000 per patient. With140,000 carotid interventions estimated for 2006, there is an enormousneed for a highly controllable thin walled deflectable guiding catheterto optimize access for this procedure as the primary goal today incarotid stenting is to minimize the catheter manipulations.

As shown in FIG. 7, which illustrates a patient 21 and the pertinentportion of the vasculature, including, for example, the left commoncarotid artery 22 which is accessed through an incision site in thegroin in a femoral artery 23. Under fluoroscopic guidance, devices arethreaded retrograde up the aorta, then antegrade down the left or rightcommon carotid artery and possible down into the internal or externalbranches of the carotid arteries. To use a steerable guide-sheath 1, aninterventionalist inserts a tapered obturator in the guide-sheath over aguidewire and inserts the tapered tip of the obturator into the femoralartery. The guide-sheath is then slid into the vessel over the obturatorand flexible guidewire. (The obturator may be removed at this point orlater.) Under fluoroscopic guidance, the interventionalist advances theguide-sheath to the carotid artery lesion region of interest. Once atthe lesion site, the interventionalist withdraws the obturator butleaves the guide and guidewire in place, or the doctor removes theobturator and guidewire together, then reinserts the guidewire throughthe guide catheter. After confirming the lesion location andguide-sheath tip location under fluoroscopy or other imaging means, thedoctor advances an interventional device through the sheath guide tostart the intervention. The interventional device can be an atherectomydevice to remove material, a balloon angioplasty device to push plaqueback against the walls of the vessel, or a stent to hold the plaque backagainst the vessel walls and keep the vessel open. In some cases, anembolic protection device is deployed beyond the lesion before theangioplasty or stenting begins. The embolic protection device istypically a trap or net or filter that is placed downstream from thelesion. Interventional manipulations can cause pieces of plaque orcalcium or thrombus to break off the lesion and proceed downstream dueto the direction of the blood flow. In the carotid intervention, thedownstream direction leads to the brain, where these emboli can lodgeand cause strokes. The embolic protection devices are designed to trapthese emboli and prevent them from entering the brain.

The deflectable guide catheter for carotid arteries should be a minimumof 6.25 (0.081″) French internal diameter and less than an 8.25 (0.108″)French outside diameter, leaving a 1 French wall thickness (thuspermitting passage of 6F devices through the deflectable guide andpermitting the deflectable guide through an 8F introducer). For some ofthe larger self-expanding nitinol stent systems, a version that is 7.25French ID and 9.25 French OD may be applicable. It is ideally at least90 centimeters total length. As shown in FIG. 7a , the deflectablesegment 5 is deflectable from a straight position to a 90-degree bend ina sweep distance D (the sweep distance is the term we use for themaximum distance between the catheter main axis and the distal tip,which in this case is the same as the radius of curvature R) of amaximum of about 1 to 3 cm, preferably about 2.5 cm (1 inch). The distaltip of the deflectable carotid catheter consists of a soft tip that isatraumatic to any tissues it encounters. The carotid guide must have asmooth and lubricious interior to easily pass devices to the targetlesion. The distal deflectable portion of the carotid guide should bestiff enough to support the interventional devices while they are beingdeployed in the carotid artery. The carotid deflectable guide shaft mustbe flexible enough in bending to track over a guidewire and obturator toreach the carotid artery from the femoral cutdown. The deflectablecarotid sheath guide should be stiff enough in torque to allow thedoctor to rotate the distal tip by rotating the proximal handle.

Each of these attributes is provided by the construction of thedeflection segment. The construction of the catheter from the distal tipto the handle consists of a composite tube made up of several layers.The very distal tip of the tube consists of a soft tip of Pebax polymer(a polyether-based polyamide). The distal deflectable segment 5 consistsof a PTFE liner that has an 0.083″ inside diameter and a 0.001″ wallthickness, a stainless steel coil with an inside diameter of 0.085″ anda wire diameter of 0.001″ impregnated with Pebax polymer (35D), a PTFEcoated stainless steel pullwire with a 0.005″ diameter, a slottednitinol deflection tube with an inside diameter of 0.098″ an outsidediameter of 0.104″ and a length of 1.25″ and slots of varying width,spacing and depth to control its behavior in curing, and a soft andrubbery pebax distal outer cover (35D) with an inner diameter of 0.104″and an outer diameter of 0.108″. The shaft proximal of the deflectionarea consists the same 0.001″ thick PTFE liner, 1 over 2 stainless steelinner braid with a flat ribbon dimension of 0.004″ wide by 0.001″ tall,an eccentric dual lumen Pebax tube of various durometers, the stainlesssteel PTFE coated pullwire, a stainless steel outer braid and Pebaxouter jacket of varying durometers whose outside diameter is 0.108″after tube construction. The lumen the pullwire travels in may berotated around the axis of the shaft of the guide to even out thepullwire length and moment of inertia of the tube with respect to theguide's main axis while the guide is being rotated by the user. This isillustrated in FIG. 4a , which shows an embodiment in which a section ofthe pull wire tube 15 is manually twisted around the inner tube 8 at alocation within the main body portion or segment. As shown in FIG. 4a ,the pull wire tube has at least one straight portion extending from thedistal end of the twisted or rotated portion, and toward the distal endof the guide sheath, and a second straight portion extending from onethe proximal end of the twisted or rotated portion, and toward theproximal end of the guide sheath.

The covered coil in the distal deflecting region of the catheter keepsthe lumen round and open during the bending process. The slotted nitinoltorque tube creates very tight bends when pulled on by the pull wire ina repeatable controllable manner. The slot pattern controls the radiusof curvature (also sweep distance), the amount of curvature and theforce required to curve the deflectable portion of the guide. The designof the slotted nitinol torque tube also controls the direction ofbending of the distal end in a repeatable manner and provides the springforce to straighten the distal end of the catheter when the pullwiretension is released. The slotted nitinol torque tube allows thesebending geometries while still transmitting torque from the handle tothe distal end of the device and providing column support to devicesinserted through the guide. The durometer of the inner and outer Pebaxportions of the tube transition from a very soft distal outer cover(35D) for 1.5 inches to a soft Pebax (50D) for 2 inches at the distalend of the non-deflecting portion of the shaft to a harder Pebax (63D)segment for 5 inches to a harder Pebax segment (72D) for the rest of theshaft. These Pebax segments allow flexibility in bending for trackingaround tight curves while providing enough column strength for thecatheter to be advanced over the guidewire and support the force of thepullwire on the distal end of the catheter during deflection. Thestainless steel braiding enhances the torque characteristics of theshaft and supports the column strength and resists buckling or kinking.The density of the braid in the braid layers and the thickness of thebraid wires may be varied to adjust the bending, buckling, and torsionalstiffness of the shaft at various sections but is generally between 25and 100 picks per inch. The proximal shaft enters the molded plastichandle through an elastomeric strain relief. The pullwire exits the sideof the shaft inside the handle and is affixed to a rotating crank. Thisrotating crank is joined to an external knob through one of the handlehalves. The torque applied to the handle of the device is transmitted tothe shaft of the device by a block that is constrained by the handlesand is glued to the shaft inside the handles. The most proximal portionof the shaft is joined to a Pebax extension, a polycarbonate extensiontube, and finally a Luer which protrudes from the proximal portion ofthe handle. Attached to this lure is a hemostatic device that allowsother devices to be placed through the guide without allowing bloodunder body pressure to escape. The hemostatic device has an infusionside arm to allow flushing of the sheath-guide while other devices areinserted within it.

To operate the device, the doctor actuates the knob to deflect thedistal end of the tube in the same direction of the knob up to 90degrees of bending. The components of the distal section of the tubekeep the lumen of the device open and round during this deflection. ThePTFE liner of the device enables other devices to slide though thecatheter easily and smoothly.

Carotid stenting may be performed with this device from either a femoralartery access or a brachial artery access site in which the deflectionmust provide a 180° turn to go up to the carotid. In addition, forcarotid access, two shapes with proximally located prefixed bends mayalso be desirable. In this situation, a thermoform bend is made suchthat the entire catheter in its undeflected shape appears like a VTECHcatheter such that the distal 1.25 to 1.5 inches of the VTECH shape isthe deflection component. Other proximal bends to the catheter, such asa deflection roughly 10 to 15 cm proximal to the distal tip in theopposite direction of the deflecting component (such that the distal endlooks like an elongated “S”) are also optional and easy to add once thedeflection characteristics and shaft diameter requirements are defined.

Renal Artery Deflectable Guide/Guide-Sheath

FIG. 8 is a schematic of a deflectable guide catheter in the bodyvasculature accessing a renal artery from a femoral access site, whileFIG. 8a illustrates the deflectable guide catheter adapted for accessinga renal artery from a femoral access site. It is estimated that 80,000procedures involving renal artery access and stenting will be performedin the United States by 2007. A deflectable Guide/Guide sheath for renalstenting is a new solution that provides physicians with the ability toaccess difficult renal arteries with severe angulation. Such arteriesare often only accessible with standard fixed guides from a brachialapproach which has far more complications. Deflectable guides canprovide back up support to advance wires and balloons and optimize theirorientation into the center of the vessel lumen.

As shown in FIG. 8, which illustrates a patient 21 and the pertinentportion of the vasculature, including the renal artery 24 which isaccessed through the vascular tree from an incision site in the groin ina femoral artery 23. The renal artery guide-sheath is ideally about 64centimeters long. The guide-sheath is inserted in the femoral arteryover a guidewire and obturator/introducer. The guide-sheath has aremovable hemostatic valve on the proximal end to control hemostasiswhile other devices are put through it. It has an internal diameter ofat least 6.25 French and an outside diameter of 8.25 French or less. Thedistal end of the renal guide-sheath should be able to bend in a curveof at least 135° from straight to access renal arteries that take offfrom the abdominal aorta at acute angles. The distal end of thesheath-guide must be stiff enough to support guidewires, ballooncatheters and stents in the renal artery without losing its position inthe ostium of the renal artery. As shown in FIG. 8a , the renal arterysheath guide should be capable of bending to the 135° angulation fromstraight within a sweep distance of 3 centimeters (about 1.25 inches).This allows the doctor to curve the distal end and access the renalartery in aortas that are narrow in diameter or calcified. The verydistal tip of the renal artery guide-sheath should be soft and may betapered on the outside diameter to allow deeper seating in the renalartery. The inside of the renal artery guide-sheath should be smooth andlubricious for the passage of guidewires, angioplasty balloons, balloonexpanding and self-expanding stents. The renal artery guide-sheathshould be stiff enough in torque to allow the doctor to get goodone-to-one rotation correspondence between the handle and the distal tipfor finding the renal artery. The distal tip of the guide-sheath isradiopaque so the doctor can see its location on fluoroscopy. Theconstruction of the distal deflectable portion of the renal artery guidesheath consists of a PTFE liner, a Pebax infused stainless steel coil, aPTFE covered pullwire, a slotted nitinol deflectable member, and a Pebaxouter jacket. The shaft proximal of the deflection tube consists of aPTFE liner, stainless steel braid, Pebax tube encasing a PTFE coveredstainless steel pullwire, stainless steel braid, and Pebax outer jacket.The handle portion of the renal artery guide-sheath is the same as thecarotid guide-sheath described above.

Abdominal Aortic Aneurysm Deflectable Guide

FIG. 9 is a schematic of a deflectable guide catheter in the bodyvasculature going from one side of the femoral aortic bifurcation to theother, while FIG. 9a illustrates the deflectable guide catheter adaptedfor crossing the femoral aortic bifurcation. This procedure is used inabdominal aortic aneurysm stent procedures. An estimated 90,000 of theseprocedures will be performed in the United States in 2007.

As shown in FIG. 9, which illustrates a patient 21 and the pertinentportion of the vasculature, including the contralateral femoral artery23R which is accessed through the vascular tree from an incision site inthe groin in a left femoral artery 23L. In abdominal aortic aneurysm(AAA) graft stenting, the doctor inserts permanent implants into theabdominal aorta and femoral arteries of the legs. The abdominal aortabifurcates into the two femoral arteries (right and left) in a “y”shape. Sometimes, the aorta is weakened and the vessel enlarges creatingan aneurysm. The stent-graft is inserted by a catheter to cover theaneurysm area and prevent any further enlarging of the aneurysm. Thegraft typically consists of a nitinol and Dacron body with an aorticportion and a left and right leg portion that lie in the femoralarteries. During one part of the procedure to install the AAA stentgrafts, the doctor needs to pass a guidewire from one femoral arteryinto the other, around the bifurcation of the femoral arteries. Thisinvolves making the guidewire turn 150° or more. For this application, adeflectable guide catheter with a minimum of 0.035″ ID (0.9 mm or about3 French) and an outside diameter of 6 French or less is desirable,although larger sizes such as would be used for renal stenting are alsoappropriate. What is necessary is that the guide be able to have a verytight turn at its distal end to redirect the guide wire down the otherleg of the AAA graft. The guide should be a minimum of 35 centimeterslong and a maximum of 90 centimeters long. As shown in FIG. 9a , thedistal end of the guide catheter should bend up to 180° in a 1 cmradius. This allows the quick and easy passage of a guidewire from onefemoral artery to the other and the connection of the AAA stent grafts.The distal shaft of the AAA guidewire passing guide consists of a PTFEliner with an ID of 0.055″ and a wall thickness of 0.001″, stainlesssteel coil with an ID of 0.058″ and a 0.001″ wire diameter embedded withPebax polymer (35D, 0.001″ wall thickness), a PTFE covered pullwire(0.0035″ diameter), a slotted nitinol tube (0.070 ID, 0.076 OD, 1.25″length, 20 to 30 slots) to control the plane and shape of the bending,and a Pebax outer jacket (35D durometer, 0.076″ ID, 0.078″ OD). The verydistal tip of the guide is a soft Pebax tip. The operation of thecatheter is a follows. The shaft construction of this guide proximal tothe deflectable portion consists of a the PTFE liner and a proximalcomposite shaft consisting of Pebax polymer, 1×2 stainless steel innerbraid, the PTFE coated stainless steel pullwire, a 1×2 stainless steelouter braid, and a Pebax (72D) outer jacket. The handle of this deviceis the same as the previously described guide.

The doctor inserts the guide or guide-sheath into the femoral arteryeither over a guidewire or a guidewire and introducer/obturator. Underfluoroscopic or other guidance, the doctor advances the steerable guideup to the bifurcation and then actuates the knob on the handle. Rotatingthe knob on the handle pulls the pullwire which is attached to the crankin the handle and the distal end of the slotted deflection tube in thedistal end of the catheter. The tension on the pullwire and theconstruction of the distal end of the catheter causes the distal end tocurve in the tight radius toward the other leg of the bifurcation. Thedoctor can also torque the catheter by the handle to twist the distalcurved end of the catheter in the abdominal aorta. Once the distal endof the catheter is pointed in the correct direction (down the otherfemoral artery), the doctor passes the guidewire up and over thebifurcation. He then snares the guidewire with a snare in thecontralateral leg and pulls it out of the opening in the contralateralartery. This allows him to complete the installation of the stent graft.This application may be used with a two-part magnet wire in whichmagnetically attracted wires are advanced both through the steerableguide catheter and through the contralateral limb such that they aredrawn to one another and no snaring of the wire is required. In such asituation one or two magnets can be used. If only one magnet is used onthe tip of one wire, then the other wire would require ferromagneticmaterials.

In other femoral artery interventions, doctors want to approach a lesionor occlusion and open it up with thrombolysis, angioplasty, atherectomy,stenting or a mechanical means of crossing the total occlusion followedby an angioplasty and stenting. Typically, these interventions takeplace in superior femoral arteries and are approached by the doctorthrough an arterial entry in the contralateral leg (side other than theleg with the blockage). In this procedure, the doctor inserts aguide-sheath into the vessel over a guidewire and dilator. Theguide-sheath has a proximal hemostasis valve that allows the insertionand withdrawal of devices through its lumen, while preventing blood fromescaping the arterial puncture (hemostasis). The doctor then uses theguide-sheath to move retrograde up the femoral artery to the bifurcationof the femoral arteries at the base of the abdominal aorta. Here, hedeflects the tip of the guide-sheath to pass the guidewire around thebifurcation, which is a tight junction. He then follows the guidewirearound the bifurcation with the guide-sheath to the location of interestin the opposite leg. There he completes the intervention with theguide-sheath providing support to the interventional devices as well assteering the guidewire and devices into specific sub-arteries off of themain femoral arteries. For this application, the inner diameter of theguide-sheath is 0.081″ and the outside diameter is 0.107″ and the lengthof the guide-sheath is between 60 and 90 centimeters (differentversions). This same device has applications for placing coils in thehypogastric arteries or internal iliac arteries during AAA graftprocedures, accessing and placing devices in the celiac trunk, anddelivering devices into he superior mesenteric artery. Devices advancedinto these vessels include guidewires, balloons, stents, infusiondevices and fluids, devices for crossing occlusions with either bluntdissection or energy delivery, coils for obstructing blood flow, andthrombectomy catheter systems which are known in the field anddeveloping.

FIGS. 9b, 9c and 9d illustrate variations of the deflectable guidecatheter adapted for crossing the femoral aortic bifurcation to supportthese procedures. The distal tip of the guide is a soft 35D Pebax softtip. The composite shaft construction of the deflectable segment 5, justproximal to the distal tip, consists of a PTFE liner with an ID of0.081″ and a wall thickness of 0.001″. Outside the liner is a stainlesssteel coil/35D Pebax composite with a round wire thickness of 0.001″ andan outside diameter of 0.090″ and a length of approximately 1.5 inches.A PTFE coated 0.0005″ pullwire rides outside of the covered coil and isattached at the distal end to a c-ring which is glued to the coveredcoil and sits in a pocket in the slotted nitinol torque tube. Theslotted nitinol torque tube has an inside diameter of 0.098″, an outsidediameter of 0.104″ and a length of about 1.5 inches. The slotted nitinoltorque tube is covered with a soft Pebax (35D) outer jacket 30 for itsfull length. The composite tubing construction proximal of thedeflectable region consists of the PTFE liner, an inner stainless steelbraid, a Pebax inner tubing (starting at 35D at the distal end andtransitioning to 72D at the proximal end in segments), the PTFE-coatedpullwire, an outer stainless steel braid, and an outer Pebax jacket thatis fused through the outer braid. The distal segment of the outer jacketis a soft 35D durometer and the jacket transitions along the main body,segment by segment to a harder 72D durometer towards the proximalportion of the catheter shaft (such that segment 50 has a hardness ofabout 50D, segment 63 has a hardness of about 63D, and segment 72 has ahardness of 72D). Each segment of Pebax is butt-welded/heat fused toeach adjoining segment to make one continuous smooth tube. The outerdiameter of the fused composite tube is 0.108″. The shaft of thecatheter enters the handle through an elastomeric strain relief aspreviously described. The proximal end of the deflection pull wire isattached to a crank and knob in the handle as previously described. Themost proximal portion of the handle is a female Luer fitting aspreviously described. In this application, a hemostatic valve isattached to the proximal Luer fitting to control the hemostasis duringthe procedure. The obturator for the Femoral Artery sheath guide is ahollow polyethylene shaft with a total length that is 4 centimeterslonger than the guide-sheath with which it is used. The obturator has aninternal diameter of 0.040″ and an outside diameter of 0.065″. Thedistal tip of the obturator tapers to an OD of 0.045″ over 4centimeters. The proximal end of the obturator has a female Luer fittingon it.

Deflectable Guide for Left Internal Mammary Access

FIG. 10 is a schematic of a deflectable guide catheter in the bodyvasculature accessing the left internal mammary artery from a femoralaccess site, while FIG. 10a illustrates the deflectable guide catheteradapted for accessing the left internal mammary artery from a femoralaccess site. The left internal mammary artery is often used duringcoronary artery bypass grafting to bypass a blockage in one of thecoronary arteries that feed the heart muscle. Over time, these bypassgrafts themselves may become occluded with thrombus or atherosclerosisand are a target for an intervention, such as angioplasty, thrombolysis,or stenting. Gaining access to the ostium of the LIMA can be verydifficult because of the angle it joins the left subclavian artery. Ifapproached from the femoral artery access point, the guide musttransverse up the aorta, into the left subclavian artery from the aortaand into the LIMA from the left subclavian artery. Although there arepre-shaped guides designed for this access, doctors still havedifficulty accessing this region. Some doctors prefer to access the LIMAfrom the radial artery, because the approach can be straighter than fromthe femoral access, but the radial arteries are typically smaller thanthe femorals which can make inserting the sheath and guide catheterdifficult.

As shown in FIG. 10, which illustrates a patient 21 and the pertinentportion of the vasculature, including the left internal mammary artery25 which is accessed through the vascular tree from an incision site inthe groin in a femoral artery 23. For this application, the LIMA guideis 90 centimeters long with an internal diameter of 4 French, anexternal diameter of 6.25 French, a 180-degree bend capability, and asweep distance D of about 1.5 centimeters (a radius of curvature R of0.75 cm), as shown in FIG. 10a . The guide must be supple enough totrack over a guidewire to reach the LIMA ostium from the femoralapproach. With the advent of new drug eluting stents a steerable guidewhich can pass 5 French stents (5.25F ID) and other devices and can beinserted through a 7F introducer (7.25F OD) are also of great value andreadily realizable through this invention.

The construction of the deflectable left internal mammary artery guideis as follows. The distal tip of the guide is a soft 35D Pebax soft tip.The composite shaft construction proximal to the distal tip consists ofa PTFE liner with an ID of 0.057″ and a wall thickness of 0.001″.Outside the liner is a stainless steel coil/35D Pebax composite with around wire thickness of 0.001″ and an outside diameter of 0.063″ and alength of approximately 1.5 inches. A PTFE coated 0.0035″ pullwire ridesoutside of the covered coil and is attached at the distal end to ac-ring which is glued to the covered coil and sits in a pocket in theslotted nitinol torque tube. (The guide wire attachment to thedeflection tube is described in Rosenman, et al., Drug DeliveryCatheters That Attach To Tissue And Methods For Their Use, U.S. Pat. No.6,511,471 (Jan. 28, 2003), hereby incorporated by reference.) Theslotted nitinol torque tube has an inside diameter of 0.070″, an outsidediameter of 0.075″ and a length of ˜1.5 inches. The slotted nitinoltorque tube is covered with a soft Pebax (35D) outer jacket for its fulllength. The composite tubing construction proximal of the deflectableregion consists of the PTFE liner, an inner stainless steel braid, aPebax inner tubing (starting at 35D at the distal end and transitioningto 72D at the proximal end in segments), the PTFE-coated pullwire, anouter stainless steel braid, and an outer Pebax jacket that is fusedthrough the outer braid. The distal segment of the outer jacket is asoft 35D durometer and the jacket transitions segment by segment to aharder 72D durometer towards the proximal portion of the catheter shaft.Each segment of Pebax is butt-welded/heat fused to each adjoiningsegment to make one continuous smooth tube. The outer diameter of thefused composite tube is 0.081″. The shaft of the catheter enters thehandle through an elastomeric strain relief as previously described. Theproximal end of the deflection pull wire is attached to a crank and knobin the handle as previously described. The most proximal portion of thehandle is a female Luer fitting as previously described.

This device can be used as a guide-sheath by the addition of ahemostatic valve on the proximal end and the use of a tapered obturatorduring introduction in the artery as previously described. The idealdimensions of the guide-sheath for this application are 0.056″ ID with a0.081″ OD. The construction method of the guide sheath is the same asthe previously described LIMA guide, but with the larger diameters.

An alternate embodiment of the deflectable LIMA guide includes apre-shape to the portion just proximal of the deflectable end. Thispre-shape makes it easier to thread the guide into the left subclavianvein. The pre-shaping is created by heating the catheter tube assemblyin that shape for a period of time and cooling the device to roomtemperature. After cooling, the shaft retains the shape. The retainingmethod for heat treating the tube can either be an internal mandrel madeof polymer or metal, or an external mold made of polymer, metal orglass.

Deflectable Guide-Sheath for Cardiac Venous Access

FIG. 11 is a schematic of a deflectable guide catheter in the bodyvasculature accessing the coronary sinus in the right atrium from avenous access site in the neck of the body, while FIG. 11a illustratesthe deflectable guide catheter adapted for accessing the coronary sinusin the right atrium from a venous access site in the neck of the body.The coronary sinus is the ostium of the venous drainage from the heartinto the right atrium. In some procedures, such as insertion ofpacemaker wires or percutaneous valvuloplasty, or infusion oftherapeutics to the heart tissue, the doctor desires to gain access tothe heart's venous system through the coronary sinus. In the usualcases, this can be done quickly, but in a significant percentage of thecases, the coronary sinus is in an unusual or hard to reach positionwhen accessed with pre-shaped guides. This is particularly true inpatients whose hearts have undergone remodeling due to disease.

As shown in FIG. 11, which illustrates a patient 21 and the pertinentportion of the vasculature, including the coronary sinus 26 which isaccessed through the vascular tree from an incision site in the jugularvein 27 of the patient. One preferred embodiment of a coronary sinusguide, shown in FIG. 11a , has a length of 60 centimeters, an internaldiameter of 7.25 French, an external diameter of 9.25 French, a 45-90degree of curvature, and a sweep distance D of 4 centimeters. Thispreferred embodiment also has a bend of 45° located about 10 centimetersproximal to the deflectable region. This bend orients the tip in thegeneral direction of the normal coronary sinus. The deflectability ofthe tip allows for the doctor to adjust the shape of the guide to suitthe specific patient anatomy.

A typical bi-ventricular pacemaker lead implantation procedure accessingthe coronary sinus proceeds as follows. The doctor inserts the steerableguide catheter with a splittable sheath introducer already in placethrough a jugular vein in the neck of the patient over a guidewire or aguidewire and obturator. The doctor advances the steerable guide to thejunction of the superior vena cava, inferior vena cava and right atriumof the heart. He steers and rotates the tip of the deflectable guidecatheter and advances and retracts the guidewire from the tip in searchof the coronary sinus. He may use radiopaque contrast and fluoroscopicguidance during this part of the procedure. Alternatively, he may use anelectrode-tipped electrophysiology catheter inside the steerable guidecatheter to look for the coronary sinus. The distinctive electricalpatterns of the conduction in the coronary sinus and also along theright atrial wall above the cardiac conduction system (AV node and HISbundle) compared to the atrial tissue will help guide placement andconfirm entry to the doctor that the EP catheter is in the sinus. Once aguidewire is placed in the sinus, the doctor will advance it down to aspecific branch of the coronary venous system that is appropriate topace the left ventricle of the heart. He then removes the guide catheterleaving the splittable or peelable introducer in place and a pacemakerelectrode is advanced through the splittable sheath to the locationchosen over the guidewire.

The construction of the deflectable coronary sinus guide catheter is asfollows. The distal tip of the guide is a soft 35D Pebax soft tip. Thecomposite shaft construction proximal to the distal tip consists of aPTFE liner with an ID of 0.096″ and a wall thickness of 0.001″. Outsidethe liner is a stainless steel coil/35D Pebax composite with a roundwire thickness of 0.001″ and an outside diameter of 0.103″ and a lengthof approximately 1.5 inches. A PTFE coated 0.006″ pullwire rides outsideof the covered coil and is attached at the distal end to a c-ring whichis glued to the covered coil and sits in a pocket in the slotted nitinoltorque tube. The slotted nitinol torque tube has an inside diameter of0.101″, an outside diameter of 0.117″ and a length of about 1.5 inches.The slotted nitinol torque tube is covered with a soft Pebax (35D) outerjacket for its full length. The composite tubing construction proximalof the deflectable region consists of the PTFE liner, an inner stainlesssteel braid, a Pebax inner tubing, the PTFE-coated pullwire, an outerstainless steel braid, and an outer Pebax jacket that is fused throughthe outer braid. The durometer for both of the Pebax components in thisshaft can be 72 D or slightly softer. The outer diameter of the fusedcomposite tube is 0.121″. The shaft of the catheter enters the handlethrough an elastomeric strain relief as previously described. Theproximal end of the deflection pull wire is attached to a crank and knobin the handle as previously described. The most proximal portion of thehandle is a female Luer fitting as previously described. The pre-shapingof the distal portion of this catheter is achieved by a heat treatmentof the composite shaft before final assembly as previously described.

An alternate embodiment of the deflectable coronary sinus guide is astraight (not pre-shaped catheter) that is pliable enough to conform tothe patient anatomy.

An alternate embodiment of the deflectable coronary sinus guide includessofter Pebax distal segments so the guide can advance over a guidewireor electrophysiology catheter into the sinus and coronary venous tree.

An alternate embodiment of the deflectable coronary sinus guide wouldhave an ID of more than 8 French and an OD of 10 French to allow an IS-1connector on a pacemaker lead to fit through it (so the guide can beused until the lead is placed distally, then the guide can be threadedover the proximal portion of the lead, leaving the distal portion of thelead undisturbed in the heart).

Deflectable Guide for Cardiac Venous Sub-Selection

FIG. 12 is a schematic of a deflectable guide sub-selecting a coronaryvein from within another deflectable guide that is accessing thecoronary sinus from a venous access site in the neck of a body, whileFIG. 12a illustrates the deflectable guide catheter adapted foraccessing a coronary vein from a venous access site in the neck of thebody, steering a guidewire or pacemaker lead into them. The coronarysinus leads retrograde to the great cardiac vein. The great cardiac veinis in communication with the middle and posterior cardiac veins of theheart. It is into these veins that the doctor wishes to position theleft ventricular pacing lead. If he can place the pacing lead in a veinthat is outside of the left ventricle, the left ventricle can be pacedby the pacemaker. This makes the pumping of the paced heart much moreeffective. One way to place this lead is to use a cardiac venoussubselector deflectable guide catheter to place a guidewire in thecorrect vein position.

As shown in FIG. 12, which illustrates a patient 21 and the pertinentportion of the vasculature, including the coronary sinus 26 and coronaryveins 28 branching off the coronary sinus, which are accessed throughthe vascular tree from an incision site in the jugular vein 27 of thepatient. The deflectable subselector guide catheter can be advancedthrough a sheath, a fixed shape guide, or through a deflectable coronarysinus guide catheter (or guide-sheath) as described above. The idealcardiac vein deflectable subselector guide is 90 centimeters long, hasan internal diameter of 0.052″, an outside diameter of 0.076″, acurvature of 90°, and a curve radius (sweep distance) of 1.0 cm. Thecardiac vein deflectable subselector guide is flexible enough to trackover a 0.018″ or 0.035″ guidewire. This flexible deflectable guide forvenous sub-selection has a very small distal curve sweep and may be usedonce access to the coronary sinus is achieved. It may also be used witha length of protruding guidewire (about 3″) to sweep the guidewire intothe coronary sinus and then follow it into the coronary sinus. This hasgreat advantages in that one less access device would be required.

The construction of the deflectable cardiac vein subselector guidecatheter is as follows. The distal tip of the guide is a soft 35D Pebaxsoft tip. The composite shaft construction proximal to the distal tipconsists of a PTFE liner with an ID of 0.052″ and a wall thickness of0.001″. Outside the liner is a stainless steel coil/35D Pebax compositewith a round wire thickness of 0.001″ and an outside diameter of 0.055″and a length of approximately 1.5 inches. A PTFE coated 0.0035″ pullwirerides outside of the covered coil and is attached at the distal end to ac-ring which is glued to the covered coil and sits in a pocket in theslotted nitinol torque tube. The slotted nitinol torque tube has aninside diameter of 0.065″, an outside diameter of 0.070″ and a length ofabout 1.5 inches. The slotted nitinol torque tube is covered with a softPebax (35D) outer jacket for its full length. The composite tubingconstruction proximal of the deflectable region consists of the PTFEliner, an inner stainless steel braid, a Pebax inner tubing (starting at35D at the distal end and transitioning to 72D at the proximal end insegments), the PTFE-coated pullwire, an outer stainless steel braid, andan outer Pebax jacket that is fused through the outer braid. The distalsegment of the outer jacket is a soft 35D durometer and the jackettransitions segment by segment to a harder 72D durometer towards theproximal portion of the catheter shaft. Each segment of Pebax isbutt-welded/heat fused to each adjoining segment to make one continuoussmooth tube. The outer diameter of the fused composite tube is 0.076″.The shaft of the catheter enters the handle through an elastomericstrain relief as previously described. The proximal end of thedeflection pull wire is attached to a crank and knob in the handle aspreviously described. The most proximal portion of the handle is afemale Luer fitting as previously described.

An alternate embodiment of the deflectable cardiac vein subselectorguide consists of a inner PTFE liner, a layer of Pebax, a PTFE coatedpullwire, an outer braid, and an outer jacket of Pebax fused through theouter braid. This construction has an even thinner wall and moreflexible shaft than the previous embodiment. It tracks better over aguidewire but has slightly less torque transmission capability.

Deflectable Guide for Coronary Artery Use

FIG. 13 is a schematic of a deflectable guide catheter in the bodyvasculature accessing the left coronary artery ostium in the aorta froma femoral arterial access site, while FIG. 13a illustrates thedeflectable guide catheter adapted for accessing the left coronaryartery ostium in the aorta from a femoral arterial access site. The leftcoronary artery is one of the main blood vessels that feeds the heartmuscle. Sometimes blockages develop in the left coronary artery or oneof its sub-branches.

As shown in FIG. 13, which illustrates a patient 21 and the pertinentportion of the vasculature, including the coronary artery 29 which isaccessed through the vascular tree from an incision site in the groin ina femoral artery 23. Doctors typically access the coronary artery with apre-shaped guide that is inserted into the femoral artery through ahemostatic sheath and advanced up the aorta over a guidewire orobturator until it reaches the aortic root. There it is manipulateduntil the guidewire and tip of the guide catheter can be lodged in theostium of the coronary artery. Next the doctor performs an angiogram tovisualize the lesion and then performs a balloon angioplasty or stentingto treat the lesions and open the target vessel. The origin of the leftcoronary artery is in the aortic root. The ideal left coronary arterydeflectable guide catheter is 4.25 French ID, 6.25 French OD, 100centimeters long, has a sweep distance of 3 centimeters, and can curveup to 135° from straight, as shown in FIG. 13a . Devices that are 5French ID and 7 French OD may also be used in the coronary arteries.

The construction of the deflectable left coronary guide catheter is asfollows. The distal tip of the guide is a soft 35D Pebax soft tip. Thecomposite shaft construction proximal to the distal tip consists of aPTFE liner with an ID of 0.057″ and a wall thickness of 0.001″. Outsidethe liner is a stainless steel coil/35D Pebax composite with a roundwire thickness of 0.001″ and an outside diameter of 0.063″ and a lengthof approximately 1.5 inches. A PTFE coated 0.0035″ pullwire ridesoutside of the covered coil and is attached at the distal end to ac-ring which is glued to the covered coil and sits in a pocket in theslotted nitinol torque tube. The slotted nitinol torque tube has aninside diameter of 0.070″, an outside diameter of 0.075″ and a length ofabout 1.5 inches. The slotted nitinol torque tube is covered with a softPebax (35D) outer jacket for its full length. The composite tubingconstruction proximal of the deflectable region consists of the PTFEliner, an inner stainless steel braid, a Pebax inner tubing (starting at35D at the distal end and transitioning to 72D at the proximal end insegments), the PTFE-coated pullwire, an outer stainless steel braid, andan outer Pebax jacket that is fused through the outer braid. The distalsegment of the outer jacket is a soft 35D durometer and the jackettransitions segment by segment to a harder 72D durometer towards theproximal portion of the catheter shaft. Each segment of Pebax isbutt-welded/heat fused to each adjoining segment to make one continuoussmooth tube. The outer diameter of the fused composite tube is 0.081″.The shaft of the catheter enters the handle through an elastomericstrain relief as previously described. The proximal end of thedeflection pull wire is attached to a crank and knob in the handle aspreviously described. The most proximal portion of the handle is afemale Luer fitting as previously described. In this application, ahemostatic valve is attached to the proximal Luer fitting to control thehemostasis during the procedure.

The deflectable left coronary artery guide can be converted to aguide-sheath by the addition of a tapered obturator and hemostaticvalve. The obturator for the coronary artery guide-sheath is a hollowpolyethylene shaft with a total length that is 4 centimeters longer thanthe guide-sheath it is used in The obturator has an internal diameter of0.027″ and an outside diameter of 0.052″. The distal tip of theobturator tapers to an OD of 0.030″ over 4 centimeters. The proximal endof the obturator has a female Luer fitting on it. The hemostatic fittingfor the coronary guide-sheath can have either a passive or activehemostatic valve. It can be supplied with a side arm to allow flushingof liquids around the inserted device if desired.

Deflectable Guide Sheath for Echographic Imaging Catheters

The deflectable guide catheter may also be adapted for use in steeringan intracardiac echo device (ICE). Intracardiac echography is a newimaging method to look at devices in the heart with ultrasound energy.The ICE device has an ultrasound emitter and detector and recreatesimages from the echoes that bounce off the devices and tissues.Typically the ICE catheter is positioned on the right side of the heartfrom the femoral vein or the internal jugular vein. The idealdeflectable guide catheter for ICE guidance is 90 centimeters long, withan internal diameter of 10 French, and external diameter of 12 French, adegree of curvature of 90° and a sweep distance of 3 centimeters.

The construction of the deflectable guide for ICE catheters is similarto those described before with a liner, covered coil, deflection tube,PTFE coated pullwire, inner braid, Pebax polymer, outer braid and aPebax outer jacket.

Deflectable Guide-Sheath for Neurological Interventions

The deflectable guide catheter can also be adapted for neurologicalinterventions. A guide for neurological intervention must be small inouter diameter, thin-walled, flexible and still pushable and torqueablebecause the vessels in the brain are very small and tortuous.Neurological guides are typically inserted in the femoral artery or theneck and advanced to the brain. There they are used to conductangiograms and to deploy devices such as coils or embolic particles totreat aneurysms or stroke. The preferred embodiment of the deflectableneurological guide catheter is 2 French internal diameter, 4 Frenchexternal diameter, 124-centimeter length, with a distal deflectableregion that can be curved to 135° through a sweep distance of 1centimeter.

The construction of the deflectable neurological guide catheter is asfollows. The distal shaft consists of a PTFE liner of inner diameter of0.026″ and a wall thickness of 0.001″. A Pebax covered stainless steelcoil of round wire diameter of 0.001″ is attached to the liner. Outsidethe covered coil is a PTFE covered stainless steel pullwire with adiameter of 0.003″. Outside of the stainless steel pullwire is a slottednitinol deflection tube of inside diameter of 0.035″ and an outsidediameter of 0.039″. The nitinol deflection tube is covered by a 35DPebax outer jacket with an inside diameter of 0.040″ and an outsidediameter of 0.045″. Proximal of the deflectable region, the shaftconstruction consists of the PTFE liner, Pebax polymer, a PTFE coatedstainless steel pullwire, stainless steel braid, and a Pebax polymerouter jacket. The Pebax polymer transitions from a soft 30D durometer atthe distal end to a hard 72D durometer at the proximal end in segmentsto allow bending and trackability while retaining pushability. Theproximal end of the device is attached to a handle with a pullwirecontrol knob as previously described.

Other applications of this thin walled steerable guide and sheath guideinvention include transjugular intrahepatic portosystemic (TIPS) shuntplacement, uterine fibroid biopsy and ablation, trans atrial septaldelivery and manipulation of devices (for pulmonary vein ablation,implantation and or recovery of devices in the left atrial appendage andperforming antegrade mitral and aortic valve manipulations andartificial valve implantation), and also for neurological access anddelivery of coils and stents.

This is a fully scalable design platform. Devices with a one French wallare readily achievable in most configurations. Devices with innerdiameters of 4.25 French that fit through 6 French Introducers, as wellas larger devices with IDs of 6.25 French that fit through 8 Frenchintroducers and which are described here are of great value and enableall of these interventions which could not be performed before.

Further, with braiding and coiling in the primary catheter body, as wellas the catheter deflection pull wire being selected fromnonferromagenetic materials such as Titanium, MP35N, and Nitinol it isclear to one with knowledge in the art that all of these devices andapplications could readily be developed to be compatible for performanceunder MRI imaging. The slotted nitinol torque tube technology applied inthese designs is perfect for MRI applications with the elimination ofthese ferromagnetic materials and the incorporation of MRI contrastagents to enhance device imaging of the catheter body and distaldeflectable torque tube cover polymer extrusions or in coatings.

Clearly for percutaneous valve implantation larger devices such as 16Fto 30F would be desired. Such large devices may have applicability forthe implantation of other large devices such as AAA grafts and presentadvantages for positioning prior to implant release.

Another application includes implantation of a self-expanding Nitinoldevice to close patent foramen ovale (PFO). Incidence of PFO in thegeneral population is as high as 25% by some estimates. PFO is ananatomical inter-atrial communication with potential for right-to-leftshunt linked to certain types of both stroke and migraine. Aself-expanding PFO closure device, such as an AMPLATZER® PFO occluder,could be delivered percutaneously over a guidewire via femoralvenipuncture and advancing the device to the foramen ovale forimplantation. In addition to delivery of PFO closure devices, othercardiac procedures may be greatly facilitated with the guide catheter,including advancement of cardiac electrophysiology catheters forelectrical mapping of the heart, pulmonary vein stent implantation,pulmonary vein ablation, mitral valve repair, percutaneous mitral valveimplantation, aortic valve repair, and percutaneous aortic valveimplantation.

By solving the problem of making a thin walled highly steerable guidecatheter and deflectable guide sheath with valve and obturator, a wholenew era of intervention has been enabled.

Thus, various embodiments of a guide catheter having a distally locateddeflectable segment with a wall thickness of 1 French or less, and witha distal end that can be curved in a tight radius of less than 1 to 2.5cm, depending on the application, while maintaining an open lumen havebeen described. While the preferred embodiments of the devices andmethods have been described in reference to the environment in whichthey were developed, they are merely illustrative of the principles ofthe inventions. Other embodiments and configurations may be devisedwithout departing from the spirit of the inventions and the scope of theappended claims.

We claim:
 1. A steerable guide sheath system adapted for delivery into apatient's vasculature, said steerable introducer sheath systemcomprising: a main tubular body having a proximal end, a distal end anda lumen extending therebetween, said main tubular body having a distaldeflectable portion that extends to said distal end and a main bodyportion that extends from said deflectable portion to said proximal end,a pull wire tube having a proximal end corresponding to the proximal endof the main tubular body, a distal end corresponding to the distal endof the main tubular body, and a pull wire lumen extending therebetween,wherein a portion of said pull wire tube is twisted or rotated aroundthe main tubular body, said twisted or rotated portion spaced distallyfrom the proximal end of the main tubular body; and wherein the pullwire tube has a distal straight segment extending distally from thetwisted or rotated portion, and a proximal straight segment extendingalong the main tubular body and extending proximally to the proximal endof the sheath from the twisted or rotated portion; and a pull wireextending through the pull wire tube between said proximal end and saiddistal end of said pull wire tube, said pull wire having a twisted orrotated pull wire portion and a distal straight pull wire segmentextending distally from the twisted or rotated pull wire portion, and aproximal straight pull wire segment extending proximally from thetwisted or rotated pull wire portion toward the proximal end of thesheath, with said distal straight pull wire segment being secured to thedistal deflectable portion to control deflection of the distaldeflectable portion of said tubular member; wherein translation of thepull wire through the twisted or rotated portion of the pull wire tubeevens out the pull wire length and moment of inertia of the main tubularbody tube with respect to a main axis of the guide while the guide isbeing rotated by the user.
 2. A steerable guide sheath system adaptedfor delivery into a patient's vasculature, said steerable introducersheath system consisting of: a main tubular body having a proximal end,a distal end and a lumen extending therebetween, said main tubular bodyhaving a distal deflectable portion that extends to said distal end anda main body portion that extends from said deflectable portion to saidproximal end, a single pull wire tube having a proximal endcorresponding to the proximal end of the main tubular body, a distal endcorresponding to the distal end of the main tubular body, and a pullwire lumen extending therebetween, wherein a portion of said pull wiretube is twisted or rotated around the main tubular body, said twisted orrotated portion spaced distally from the proximal end of the maintubular body; and wherein the single pull wire tube has a distalstraight segment extending distally from the twisted or rotated portion,and a proximal straight segment extending along the main tubular bodyand extending proximally to the proximal end of the sheath from thetwisted or rotated portion; and a single pull wire extending through thesingle pull wire tube between said proximal end and said distal end ofsaid pull wire tube, said pull wire having a twisted or rotated pullwire portion and a distal straight pull wire segment extending distallyfrom the twisted or rotated pull wire portion, and a proximal straightpull wire segment extending proximally toward the proximal end of thesheath from the twisted or rotated pull wire portion, with said distalstraight pull wire segment being secured to the distal deflectableportion to control deflection of the distal deflectable portion of saidtubular member; wherein translation of the pull wire through the twistedor rotated portion of the pull wire tube evens out the pull wire lengthand moment of inertia of the main tubular body tube with respect to amain axis of the guide while the guide is being rotated by the user.